#!/usr/bin/perl -w

use strict;
use DBI;

my $L1 = 10;
my $L2 = 20;

sub do_error($) {
   exit(1);
}

sub readable {
	my $size = shift;
	my @add = qw( B KB MB GB TB );
	my $i ;
	for ($i = 0; $i < 5;$i++) { 
		if ( int($size / 1024) > 0 ) {
			$size = $size / 1024;
		} else {
			$size = 0.01*int(0.5+ $size/0.01) . " " . $add[$i];
			last;
		}
	}
	return $size;
}

if(scalar(@ARGV) < 4) {
	print "Usage: $0 <mysqluser> <mysqlpass> <mysqldb> <destination path> [delete]\n";
	printf"   if [delete] is given, attachments will be removed from the database, to free storage\n";
	exit(1);
}

my ($user,$pass,$dbname,$basepath,$delete) = @ARGV;

my $db = DBI->connect("dbi:mysql:$dbname", $user, $pass);

my $res; 
my $sth;
my $rows;
my @row;

if (!defined($db)) {
	print "did not connect to mysql\n";
	exit(1);
}

$res = $db->do("set character_set_client=utf8;");
if(!$res) {
  do_error(1);
}
$res = $db->do("set character_set_connection=utf8;");
if(!$res) {
  do_error(1);
}
$res = $db->do("set character_set_results=utf8;");
if(!$res) {
  do_error(1);
}
$res = $db->do("begin;");
if(!$res) {
  do_error(1);
}

$sth = $db->prepare("SHOW TABLE STATUS WHERE name = 'lob'");
$sth->execute() || die $DBI::errstr;
if ($sth->rows == 0) {
	print "Can't get attachment size.\n";
	exit(0);
}

@row = $sth->fetchrow_array();
if (! defined ( $row[0] ) ) {
	print "Table status failed.\n";
	exit(0);
}
my $dbsize = $row[6];
print "The size of all attachments in the database is: ". $dbsize." Bytes (". readable($dbsize) . ")\n";

my $free = `df -P -B1 $basepath | tail -1 | awk '{print \$4}'`;
chomp($free);
print "Available space is: " .  $free . " Bytes (" . readable($free) . ")\n";

if ( $dbsize >= $free ) {
	print "Not enough space left on device.\n";
	exit(0);
}


print "Finding all attachments...\n";
$sth = $db->prepare("SELECT distinct(instanceid) FROM lob");
$sth->execute() || die $DBI::errstr;;

if ($sth->rows == 0) {
	print "No attachments found.\n";
	exit(0);
}

print "Processing ".$sth->rows." attachments\n";

while(@row = $sth->fetchrow_array()) {
	my @data;
	my $path = $basepath."/".($row[0] % $L1)."/".(($row[0] / $L1) % $L2);
	my $filename = $path."/".$row[0];

	system("mkdir -p ".$path) == 0 or die("Unable to create attachment directories");

	if ( -s $filename ) {
		next;
	}
	open(AFILE, ">".$filename) or die("Unable to open new attachment file");

	my $sth2 = $db->prepare("SELECT val_binary FROM lob WHERE instanceid=".$row[0]." ORDER BY chunkid");
	$res = $sth2->execute();
	if(!$res) {
		print "  Unable to extract attachment ".$row[0]."\n";
		next;
	}

	while (@data = $sth2->fetchrow_array()) {
		print AFILE $data[0] or die("Not all data could be retrieved from attachment ".$row[0]);
	}
	close(AFILE);
}

print "Done.\n";

if (defined($delete) && $delete) {
	print "Deleting attachments from database...\n";
	$sth = $db->prepare("DELETE FROM lob");
	$sth->execute() || die $DBI::errstr;
	print "Done.\n";
}

print "Remember to correct the ownership of the files for kopano to access, when Kopano is not running as root\n";

$db->do("commit;");
